Method For Routine Identification Research Articles

International Collaborative Evaluation of the ATB 32 Staph gallery for Identification of the Staphylococcus Species

This international collaborative study evaluates a new system (ATB 32 Staph) for the identification of staphylococci taking into account the new novobiocin-sensitive and -resistant species reported. This study involved eight laboratories and 792 strains were tested. The reproducibility obtained for the cumulative results of the inter- and intea-laboratory tests was more than 90%. For 713 strains relevant of a species 95.5% were correctly identified by the system. Eight strains (1.2%) were misidentified and 24 strains (3.3%) were not identified. For 79 strains initially considered as not-classified, 62% were identified at the species level by the new system. The newer ATB 32 Staph gallery is a performant and useful method for routine identification of the currently described staphylococci species from clinical and animal origin.

A routine method for the analysis of mononitro-PAH in immission and emission samples

A routine method for the identification and quantification of mononitrated polycyclic aromatic hydrocarbons in environmental samples has been developed. Micro-scale liquid-liquid partition between dimethylformamide and cyclohexane and HPLC on normal-phase silica gel columns are used for clean-up of samples. This preconcentration scheme is time-saving and uses a minimal amount of solvents. Identification and quantification are performed by GC/ECD and GC/MS in the “selected ion monitoring” mode. The analytical scheme has been optimized under use of standard substances by variation of several parameters in different steps of the analysis. The method was applied to the NBS Reference Material SRM 1649 “Urban Dust”, to urban air samples from the city of Vienna as well as to combustion emissions.

Identification of the substantia nigra pars lateralis in the macaque using cytochrome oxidase and fiber stains

Classically, the substantia nigra is divided into three subdivisions, the pars compacta, the pars reticulata, and the pars lateralis. The purpose of the present study was to develop methods for routine identification of the non-compacta subdivisions in the macaque monkey. First, the pars reticulata and pars lateralis were identified based on their Nissl features. Second, nearby cytochrome oxidase and Gallyas fiber stained sections were examined for these two subdivisions. In both stains, a dorsolateral region could be identified to contain large fiber bundles. This region is coextensive with the pars lateralis as identified in Nissl-stained preparations. Lastly, we examined the complete extent of the pars lateralis using the cytochrome oxidase procedure. We conclude that in the macaque monkey the pars lateralis can be identified as a distinct nigral subdivision by using cytochrome oxidase and fiber staining techniques.

A Routine method for identification and quantitative determination by gas—liquid chromatography of galacturonic acid in pectic substances

AbstractA semi‐micro method is described for the determination by gas‐liquid chromatography (g.l.c.) of galacturonic acid in pectic substances which has been solubilised in aqueous ammonium oxalate. Galacturonic acid, liberated by hydrolysis with polyanhydrogalacturonase [poly‐(1,4‐α‐D‐galacturonide) glycanohydrolase; EC 3.2.1.15] and then converted to the L‐galactono‐1,4‐lactone via potassium borohydride reduction and lactonisation using methanolic hydrogen chloride. The derived lactone was analysed by g.l.c. as the trimethylsilyl derivative, and was easily distinguished from the glucuronic acid reduction product, L‐gulono‐1,4‐lactone. The method was applied to the analysis of pectic materials in leaflets, petioles, and stem of three tropical legumes, and also to the polygalacturonic content of commercial pectin preparations. The possibility of simultaneous determination of starch extracted with pectin is also discussed.

BARLEY CULTIVAR IDENTIFICATION BY SCANNING ELECTRON MICROSCOPIC ANALYSIS OF THE RACHILLA

Rachillae from 30 Canadian-grown barley cultivars were examined with a scanning electron microscope (SEM). Epicuticular wax crystal formations and cuticular ridges were prominent morphological features observed on the rachilla main stem. Distinct variations among cultivars, in the patterns of wax crystals and in the regularity, width and prominence of cuticular ridges were utilized alone or in combination to differentiate among cultivars. The ability to differentiate among cultivars was improved substantially by stereo SEM analysis of those morphological features. Twenty-six of the 30 cultivars studied could be identified by SEM analysis of the rachilla main stem. The remainder was divided into two indistinguishable pairs which could be distinguished from the other 26 cultivars. The effect of environment on the visual appearance of the epicuticular wax formations and cuticular ridges was studied. As a rule, environmental influence on these morphological features was not of sufficient significance to interfere with the identification of barley cultivars. SEM analysis of the rachilla would not be useful as a routine identification method and its use would be restricted to the laboratory. However, this technique would serve as a qualitative identification procedure which could be utilized to assist in the identification of barley cultivars which are impossible or difficult to distinguish by conventional means.

The aggressive and non-aggressive strains of Ceratocystis ulmi have different temperature optima for growth

The aggressive and non-aggressive strains of Ceratocystis ulmi exhibit markedly different temperature-growth responses in vitro . The optimum temperature of the aggressive strain (both EAN and NAN races) was 20–22°C and that of the non-aggressive strain was c. 30°. The upper limit for growth of the EAN aggressive was c. 32% of the NAN aggressive c. 33°, and of the non-aggressive strain c. 35° Two temperatures, 20 and 33°, are now recommended for separating the strains on the basis of growth-rate. The ranking order of the strains at 20° is the reverse of that at 33° and this provides a qualitative method for routine strain identification. The significance of the different temperature-growth responses of the two strains is discussed.

A leaf dip method for routine identification of plant viruses using the latex agglutination test

A description is presented of a simplified procedure for the serological diagnosis of plant viruses which utilizes the high sensitivity of the latex test. Small pieces of the plant examined are soaked in a drop of water, buffer, or directly in the sensibilized antiserum. Following the reaction with the antiserum the virus is evidenced by visual evaluation of the presence of agglutination. The procedure is applicable for routine serological diagnosis; it demonstrates even small virus concentrations and is as reliable as the normal procedure of the latex test. Using this simplified procedure the following viruses were demonstrated in various host plants: X-, Y-, S-, and M-virus of potato, the carnation mottle virus, and the tomato bushy stunt virus.

An improved method for the routine identification of faecal viruses using ammonium sulphate precipitation

An improved method for the routine identification of faecal viruses using ammonium sulphate precipitation

Routinemethode zur dünnschichtchromatographischen identifizierung der pestizidrückstände aus des klassen der triazine, carbamate, harnstoffe und uracile

Routine method for identification of pesticide residues of triazine, carbamate, urea, and uracil type compounds by thin-layer chromatography For a reliable and reproducible identification by thin-layer chromatography ten systems for the separation and detection of sixty-one pesticides—mostly herbicidal—have been developed, based on a general technique described previously. Two or three systems for each group of pesticides enable the analyst to differentiate almost all of the sixty-one compounds unambiguously, only three pairs of substances remaining unresolved. These results can be obtained by statistical evaluation of the variabilities in the R F values of these systems.

Verfahren zur erzielung gut reproduzierbarer R F-werte bei serienmässig durchgeführter dünnschicht-chromatographie : Routinemethode zur identifizierung insektizider chlorkohlenwasserstoffe

A method yielding high reproducible R F values suitable for thin-layer chromatography in series. Routine method for identification of chlorinated hydrocarbon pesticides A general method is described. By using preferably monocomponent solvents R F values of high reproducibility are obtainable. Maximum deviations from the mean value are not more than 3 hR F , mean deviations from the mean values are equal to 0.8 hR F , standard deviations are of ± 1.2. The technique needs cheap and simple laboratory equipment only, and a large number of plates may be chromatographed daily in routine analysis. This method is applied to the identification of at least sixteen chlorinated hydrocarbon pesticides by their R F values.

Identification of Mycoplasmas of Human Origin

SUMMARY: Fifty-five strains of the genus Mycoplasma were isolated from sputam of 95 patients suffering from various respiratory tract diseases. The polyacrylamide gel electrophoretic method was used to identify the isolated strains, in addition to the conventional biochemical methods and growth-inhibition by antisera. The electrophoretic patterns of the isolated strains were compared with those of known human mycoplasmas. The electrophoretic patterns obtained were species specific and highly reproducible. The results of the identification of the isolated strains by the gel electrophoretic method correlated well with those of the growth inhibition test. It is suggested that polyacrylamide gel electrophoresis of whole cell proteins might become a useful routine method for identification of mycoplasmas. The most prevalent Mycoplasma found in the sputa was Mycoplasma salivarium, only four strains were identified as M. orale type 1 and one strain as M. pneumoniae. One strain was similar to, but not identical with, M. salivarium. The three oral anaerobic mycoplasmas (M. salivarium, M. orale types 1 and 2) showed a certain similarity when examined by the gel electrophoretic method, they may be genetically related to each other.